Accepted endodontic practice typically includes several steps. Initially, a proper coronal access to the canal is obtained and, where possible, the patient relieved of pain. Next, the cleaning of the canal undergoes enlargement and tapering, and all debris and fluid removed from it. Lastly, for obturation, the tooth must be free of pain. The canal is then freshly irrigated, dried, and the root canal cement is applied. A master cone and accessory cones of gutta percha are laterally condensed to fill the canal. A permanent coronal restoration is then placed to finish the procedure.
Most failures in endodontics result from the incomplete sealing of the apical area, the porous dentinal tubules in the lateral walls of the canal, or both. There has been a constant effort to find an adequate material and method to improve the final seal and prevent the communication of substances from the root canal and its apex to the structure surrounding both.
The systematic study of different sealants has appeared in articles by P. M. Spradling et al., Journal of Endodontics, Vol. 8, 1982, pages 543 to 549 and D. Oerstavik, International Endodontic Journal, Vol. 16, 1983, pages 59 to 63. These articles indicate some inconsistency with other studies and between themselves as well as leaving doubt as to the most desired material.
Various glues formed from cyanoacrylates have undergone study in the oral environment. Y. Fukushi et al. examined it as a glue for resin restorations in Journal of Dental Research, Vol. 59(4), 1980, pages 662 to 699; M. J. Mitrosky, looked at cyanoacrylates as a bonding agent for the usual fillings as well as restorations in Quintessence International, Vol. 9, September, 1981, pages 871 to 874; and G. M. Brauer et al., Journal of Dental Research, Vol. 58, 1979, pages 1900 to 1907, looks at the use of cyanoacrylates to bond acrylic resins to dentine. These studies report varying results for cyanoacrylates as a bonding agent in the moist oral environment.
Many materials have found use as a sealer and as a filling material in endodontic therapy. However, none have obviated the desire for materials with improved sealing and bonding properties.